1. Field of Invention
This invention is directed to systems and methods for filtering and viewing collaborative indexes of annotations of one or more multimedia or video streams.
2. Description of Related Art
Digital multimedia recordings of meetings, seminars, and classes are becoming more widely available. Systems and methods for taking notes with respect to various sorts of multimedia recordings using laptops, pen-based notebook computers, personal digital assistants and the like, have been developed. The NOTELOOK and LITEMINUTES products, by Fuji Xerox Co., Ltd., are examples of such systems and methods. Further, various ways of annotating interesting points in a meeting or other video stream have been devised using anything from the devices described above to key tags or wireless telephones. These annotations are generally time stamped and/or associated with video streams for browsing through the video streams and/or retrieving specific portions of the video streams.
Using the above described technologies, annotations can be created by different people, using different devices, and sometimes in a distributed setting. Integrating these annotations can create a valuable tool for later viewing of a video stream, or viewing of the video stream by a different user.
A method of viewing audio-video presentations is described by He et al. in “Auto-Summarization of Audio-Video Presentations,” Proceedings of ACM MultiMedia '99 (1999). In He, the access patterns of users of an audio-visual presentation are used to summarize the presentation. The importance of a particular segment of an audio-visual presentation is determined, for example, based upon the number of viewers who stopped or started the presentation at that point or segment at a given time or within a given time period. Alternatively, the importance of a particular segment of an audio-visual presentation can be determined based simply upon the number of viewers who have viewed that segment of the presentation.
Another example of a method of viewing a video presentation is presented in Li et al., “Browsing Digital Video,” Proceedings of CHI 2000 (2000). In Li, students were asked to summarize the main points of a classroom presentation. A time constraint was placed on the students so that they could not watch the entire video. Li discovered that users who employed a table of contents computed by slide changes during the classroom presentation were able to view a greater portion of the presentation. The method of viewing provided by Li relies on intrinsic features of the presentation (slide changes).
Correia et al., “Active Video Watching Using Annotation,” ACM Multimedia '99 (1999), alludes to the possibility of integrating content provided by various users with regard to a video presentation. Correia states that with suitable tools, combining content provided by a plurality users, with respect to a single audio or visual presentation, would enable the creation of participatory communities. Thus, viewers of a particular television program or audio presentation can share opinions, ideas and comments, using the medium that originated the opinion, idea or comment.
Various systems and methods for weighting a document based on its popularity are known. For example, search engines, such as GOOGLE®, weight textual documents (web pages) based on the number of users who access or use the particular document. Likewise, online retailers, such as AMAZON.COM®, suggest books based upon the number of e-consumers who purchase the book. Resnick et al., “An Open Architecture for Collaborative Filtering of Netnews,” Proceedings of CSCW '94 (1994) presents the concept of filtering to recommend popular documents, as applied to Usenet News. In Goldberg et al., “Using Collaborative Filtering to Weave an Information Tapestry,” CACM, 35(12), pp 51-60 (December 1992), collaborative filtering is employed to emphasize popular e-mail messages from a larger collection. In Balabanovic et al., “Content-Based, Collaborative Recommendation,” CACM, 40(3), pp 66-72 (1997), a method for providing recommendations of popular web pages is suggested. Hill et al., “Recommending and Evaluating Choices in a Virtual Community of Use,” Proceedings of CHI '95 (1995) describes a method of recommending particular movies or music, based upon the popularity of the item. In these systems, users state preferences for an entire item or document, i.e. a compact disc, a DVD or a book, often through explicit ratings or scores. Some methods consider various forms of user activity as an implicit preferential statements.
Systems and methods are also known for weighting particular portions of a document based on its popularity. He proposes methods for weighting a particular portion of a video presentation. According to He, a portion of video is deemed to be more ‘valuable’ based upon the number of times an entry in the table of contents is used to select that specific segment of the video. In He's method, the most popular segments of a video are assumed to contain the most significant information.
Various systems and methods for viewing annotated documents are also known. For example, U.S. patent application Ser. No. 09/951,733, incorporated herein in its entirety by reference, describes systems and methods for emphasizing particular annotations in an annotated document. The function of emphasizing annotations is performed by considering the frequency and type of annotation made, and whether comments are included or associated with the annotation. The above-described systems and methods permit a user to view a document that has been annotated, and readily view portions that are determined to merit emphasis.